I just did 57 estate pipes and it kicked my butt. Fingers hurt for two weeks. Here is what I do.
Two spoonfuls of Oxyclean in a Tupperware bowl of water. Cover any stamps or metal or decor not made of stem material in petroleum jelly. Soak stems for 1 hour. If they turn white or green or brown don't freak out!
I rinse them and them I take bristled pipe cleaners and soak them in Everclear and run them down the air hole until they come out clean. Then I follow up with Briar Fresh.
Next I take a magic eraser and scrub the stem. The important thing here is to scrub and scrub and scrub until no more yellow comes off onto the eraser. I learned the hard way. In certain light the stem may look black but in bright light you may see the discoloration of you don't get that oxidation off. I use my iPhone light to check it over. Once that is done I use wet automotive sandpaper in various steps (finer as you go). It helps remove oxidation and chatter. Micromesh is a great option too.
Final step is I use Decatur Haze Away and microfiber clothes to start hand buffing. It removes any leftover oxidation. Then I take a low speed buffer and hit it with Decatur Shine Bright followed by carnuba wax. Final step
Is a light coat of Decatur Stem Oil. Here is a finished example.
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